/**
 * Copyright 2006 Brad Reynolds
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.leeloo.databinding.internal.ui;

import org.eclipse.jface.dialogs.IInputValidator;
import org.leeloo.core.Tag;

/**
 * Validates use input for a tag.
 * 
 * @author Brad Reynolds
 */
public class TagFilterValidator implements IInputValidator {
    /**
     * Error to display.
     */
    private static final String error = Messages.getString("TagFilterValidator.message_format"); //$NON-NLS-1$
    
    /**
     * Constructs a new instance.
     */
    public TagFilterValidator() {
    }
    
    /**
     * Validates the user input against {@link Tag#NAME_VALUE_PATTERN} returning {@link #error} is invalid.
     * 
     * @see org.eclipse.jface.dialogs.IInputValidator#isValid(java.lang.String)
     */
    public String isValid(String newText) {
        return (Tag.NAME_VALUE_PATTERN.matcher(newText).matches()) ? null : error;
    }
}